1. Field of the Invention
The present invention relates to a buckle assembly for vehicle seat belt and is more particularly directed to improvements in such a buckle assembly.
2. Description of the Prior Art
Various improvements have been proposed for buckle assemblies for vehicle seat belt. All of the known buckle assemblies for vehicle seat belt have a common basic structure comprising a tongue and a locking mechanism for locking the tongue in a predetermined position. The locking mechanism or device generally includes a base member, a locking member normally biased in its tongue locking direction by bias means disposed in the base member, operating means for actuating the locking member and cover means for enclosing and supporting all of the members. One of the most important problems involved in the buckle assembly of the above structure is found in assembling. All of the structural members must be assembled together properly between the base and cover so as to form a buckle assembly easily and conveniently operable. However, structural members and parts of the known buckle assembly are complicated in form and structure and they each need manual work in assembling. This is laborious and time consuming and therefore the manufacturing cost becomes high. In addition, the products lack uniformity and the operability thereof is not so good.
Another problem is found in the position at which locking member operating means must be mounted. Means for operating the locking member is usually composed of a push button directly engaged with the locking member and being manually operative such as with the operator's finger. Since the push button is to be engaged directly with the locking member, the former has to be mounted in the vicinity of the latter, which limits the freedom of the push button mounting position. It is not always allowable, therefore, to dispose the exposed surface part of the push button in a position convenient for the operator to push the exposed surface part with his finger. This makes the operability of the push button unsatisfactory. Furthermore, since the force applied to the push button by the operator is directly used to operate the locking member, the unlocking and disconnecting action of the buckle assembly may be done only in an unsatisfactory manner.